Compositions and methods for systemic administration of sequences encoding bone morphogenetic proteins

ABSTRACT

Compositions and methods for systemic administration of DNA encoding bone morphogenic proteins for promotion of osteogenesis are disclosed. The compositions and methods of the invention may be utilized for fracture repair. The invention further discloses compositions and methods for systemic administration of bone morphogenetic proteins for promotion of osteogenesis. These compositions and methods may be used in bone fracture healing and repair. These composition of the invention may be further utilized in increasing bone mineral density.

This application claims priority from U.S. provisional application Ser.No. 60/295,153.

BACKGROUND OF THE INVENTION

The present invention relates to the field of tissue repair. Moreparticularly, the present invention relates to compositions an,d,methodsfor systemic administration of sequences encoding osteogenic proteins.The invention also includes methods and compositions for the systemicadministration of osteogenic proteins for promotion of osteogenesis. Thecompositions and methods promote osteogenesis and therefore uses includefracture healing and repair and acceleration of fracture healing. Thesemethods and compositions may also be used for the treatment ofosteoporotic bone and or the prevention and treatment of osteoporosis.

SUMMARY OF THE INVENTION

The present invention is directed to compositions and methods forsystemic administration of DNA sequences encoding osteogenic proteins.The invention also includes methods and compositions for the systemicadministration of osteogenic proteins or peptides for promotion ofosteogenesis. The compositions and methods may be used to promotefracture healing and repair and acceleration of fracture healing. Thesemethods and compositions may also be used for the treatment ofosteoporotic or osteopenic bone and or the prevention and treatment ofosteoporosis.

The osteogenic proteins and DNA sequences encoding them are preferablyselected from the family of proteins known as the transforming growthfactors-beta (TGF-β) superfamily of proteins, which includes the bonemorphogenetic proteins (BMPs), activins and inhibins. Most preferably,the active agent includes at least one DNA sequence encoding proteinselected from the subclass of proteins known generally as BMPs, whichhave been disclosed to have osteogenic activity, and other growth anddifferentiation type activities. These BMPs include BMP proteins BMP-2,BMP-3, BMP-4, BMP-5, and BMP-7, BMP-10, BMP-12 and BMP-13, BMP-15,BMP-16, further described below. The osteogenic agent is most preferablythe DNA sequences encoding BMP-6 or BMP-6 proteins or peptides. The DNAand protein sequence and methods for producing BMP-6 are disclosed inU.S. Pat. Nos. 5,187,076, 5,459,047 and 5,849,880 and in U.S. Ser. No.09/189,157, the disclosures of which are herein incorporated byreference. Other agents and the DNA sequences encoding them which arecapable of inducing bone growth or fracture repair or increasing theformation of bone tissue may also be utilized.

The invention therefore provides compositions and methods for promotingosteogenesis wherein the composition comprises a DNA sequence encodingan osteogenic protein in an injectable formulation suitable for systemicadministration. In preferred embodiments the osteogenic protein is abone morphogenetic protein (BMP). Such compositions are useful forfracture healing and repair. These compositions may be used forincreasing bone mineral density. Osteoporotic or osteopenic bone isoften characterized by suboptimal bone density and therefore thecompositions and methods may be used for increasing bone mineral densityand treating osteoporosis.

In a preferred embodiment, the invention features a composition andmethod for promoting fracture repair wherein the composition comprises aDNA sequence encoding BMP-6 and is employed in a method involvingsystemic administration to a patient in need of fracture repair. The DNAand protein sequence and methods for producing BMP-6 are disclosed inU.S. Pat. Nos. 5,187,076, 5,459,047 and 5,849,880 and in U.S. Ser. No.09/189,157, the disclosures of which are herein incorporated byreference. In other embodiments the following BMPs may besuitable:BMP-2, BMP-3, BMP-4, BMP-5, BMP-7, BMP-10, BMP-12 and BMP-13,BMP-15, and BMP-16, further described below.

In the present invention, the vectors used for incorporation andexpression of the DNA are preferably viral in origin, particularlyadenoviruses, as well as retroviruses. Adenoviruses are advantageous inthat they do not require cells in the state of proliferation, and have ahigh efficiency rate of infection both in vitro and in vivo, whereasretroviruses are more often suitable for in vitro infection.Adenoviruses also offer high levels of transgene expression and theability to achieve high titers. These advantages make adenoviruses moresuitable for primary cells, cell lines and direct in vivo transduction.In addition, expression of the transgene is transient and the adenoviralvector does not integrate into the cell genome, making the vectors saferfor use. All generations of recombinant adenoviruses are suitable,including the present generation, (E1 deleted), and new generationswhich have reduced antigenicity (E1, E3, E4 deleted viruses, or E1, E4deleted and E3 overexpressed). Smith (1995); Dunbar (1996); Roemer(1992); Graham (1991); Kozarsky (1993); and Ilan (1997). The disclosureof each of the above publications is hereby incorporated by referencefor the contents thereof.

The expression of the genes which are expressed in the present inventionmay be constitutive or controlled. Controlling the expression can beachieved by external control by means of regulatory elements, such aswith an inducibly controlled promoter, for example, a tetracyclinecontrolled promoter, as further described herein, or by using regulatoryelements from tissue specific or temporally specific genes to direct theexpression only to certain specified differentiation pathways or atcertain stages in differentiation. For example, the osteocalcin promotermay be used for induction at late stages of bone formation andcalcification.

In a preferred embodiment the BMP DNA sequence, preferably BMP-6 iscontained on an adenovirus vector comprising an injectable formulationsuitable for systemic administration. This composition may be used in amethod comprising systemic administration a therapeutically effectiveamount of the composition to a patient in need of fracture repair.

The invention further provides methods and compositions for promotingosteogenesis wherein the composition comprises an osteogenic protein. Inpreferred embodiments the osteogenic protein is a bone morphogeneticprotein (BMP). Such compositions are useful for fracture healing andrepair. These compositions may be used for increasing bone mineraldensity. Osteoporotic or osteopenic bone is often characterized bysuboptimal bone density and therefore the compositions and methods maybe used for for increasing bone mineral density and treatingosteoporosis.

In a preferred embodiment, the invention features a composition andmethod for promoting fracture repair wherein the composition comprisesBMP-6 and is employed in a method involving systemic administration to apatient in need of fracture repair.

In other embodiments the following BMPs may be suitable: BMP-2, BMP-3,BMP4, BMP-5, BMP-7, BMP-10, BMP-12 and BMP-13, BMP-15, and BMP-16,further described below.

In preferred embodiments, the active agent is one or more proteinsselected from the group of proteins known as the Transforming GrowthFactors-Beta (TGF-β) superfamily of proteins, preferably selected fromthe Bone Morphogenetic Proteins (BMPs), the Growth and DifferentiationFactors (GDFs), as well as other proteins, as described more fullyherein. Osteogenic proteins, DNA sequences, compositions and methods forproducing them, useful in the present invention, are those comprisingthe BMP proteins BMP-2, BMP-3, BMP-4, BMP-5, BMP-6 and BMP-7, disclosedfor instance in U.S. Pat. Nos. 5,108,922; 5,013,649; 5,116,738;5,106,748; 5,187,076, 5,459,047, 5,849,880; and 5,141,905; BMP-8,disclosed in PCT publication WO91/18098; and BMP-9, disclosed in PCTpublication WO93/00432, BMP-10, disclosed in PCT application WO94/26893;BMP-11, disclosed in PCT application WO94/26892, or BMP-12 or BMP-13,disclosed in PCT application WO95/16035, or BMP-15, disclosed in PCTapplication WO96/36710 or BMP-16, disclosed in co-pending patentapplication Ser. No. 08/715/202, filed Sep. 18, 1996.

Other DNA molecules and the proteins which they encode which may also beuseful include those encoding Vgr-2, and any of the growth anddifferentiation factors [GDFs], including those described in PCTapplications WO94/15965; WO94/15949; WO95/01801; WO95/01802; WO94/21681;WO94/15966; and others. Also useful in the present invention may be BIP,disclosed in WO94/01557; and MP52, disclosed in PCT applicationWO93/16099. The disclosures of all of the above applications are herebyincorporated by reference for the disclosure contained therein.

Other DNA molecules and the proteins which they encode which may beuseful, in addition to DNA encoding a BMP protein, include DNA moleculesencoding other therapeutically useful agents including growth factorssuch as epidermal growth factor (EGF), fibroblast growth factor (FGF),transforming growth factor (TGF-α and TGF-β), hedgehog proteins such assonic, indian and desert hedgehog, parathyroid hormone and parathyroidhormone related peptide, cadherins, activins, inhibins, and IGF, FSH,frizzled, frzb or frazzled proteins, PDGF and other endothelial growthfactors, BMP binding proteins such as chordin and fetuin, estrogen andother steroids as well as truncated versions thereof, and transcriptionfactors such as wnt proteins, mad genes and cbfa.

The disclosures of the above identified applications are herebyincorporated herein by reference. The unique inductive activities ofthese proteins, along with their presence in bone, suggests that theyare important regulators of bone and cartilage repair processes, and maybe involved in the normal maintenance of bone tissue.

BRIEF DESCRIPTION OF THE DRAWING

FIG. 1 is an illustration of the fracture apparatus utilized in theclosed-femur fracture model

DETAILED DESCRIPTION OF THE INVENTION

The invention provides compositions and methods for promotingosteogenesis. The compositions of the invention comprise a DNA sequenceencoding an osteogenic protein in an injectable formulation suitable forsystemic administration. In preferred embodiments the osteogenic proteinis a bone morphogenetic protein (BMP). Such compositions are useful forfracture healing and repair. These compositions may be used forincreasing bone mineral density. Osteoporotic or osteopenic bone isoften characterized by suboptimal bone density and therefore thecompositions and methods may be used for for increasing bone mineraldensity and treating osteoporosis.

In a preferred embodiment, the invention features a composition andmethod for promoting fracture repair wherein the composition comprises aDNA sequence encoding BMP-6 and is employed in a method involvingsystemic administration to a patient in need of fracture repair. The DNAand protein sequence and methods for producing BMP-6 are disclosed inU.S. Pat. Nos. 5,187,076, 5,459,047 and 5,849,880 and in U.S. Ser. No.09/189,157, the disclosures of which are herein incorporated byreference. In a further preferred embodiment the BMP DNA sequence iscontained on an adenovirus vector.

In other embodiments the following BMPs may be suitable: BMP-2, BMP-3,BMP-4, BMP-5, BMP-6 and BMP-7, BMP-9, BMP-10, BMP-12 and BMP-13, BMP-15,BMP-16, further described herein.

The invention further provides methods and compositions for promotingosteogenesis wherein the composition comprises an osteogenic protein.These proteins may be chemically modified to provide an injectableformulation suitable for systemic administration. Such modification isknown to those skilled in the art. In preferred embodiments theosteogenic protein is a bone morphogenetic protein (BMP) suitable forsystemic administration. Such compositions are useful for fracturehealing and repair. These compositions may be used for increasing bonemineral density. Osteoporotic or osteopenic bone is often characterizedby suboptimal bone density and therefore the compositions and methodsmay be used for for increasing bone mineral density and treatingosteoporosis.

In a preferred embodiment, the invention features a composition andmethod for promoting fracture repair wherein the composition comprisesBMP-6, described above, and is employed in a method involving systemicadministration to a patient in need of fracture repair.

In other embodiments the following BMPs may be suitable: BMP-2, BMP-3,BMP-4, BMP-5, BMP-7, BMP-9, BMP-10, BMP-12 and BMP-13, BMP-15, BMP-16,further described below.

The invention therefore provides compositions and methods for promotingosteogenesis wherein the composition comprises a DNA sequence encodingan osteogenic protein. In preferred embodiments the osteogenic proteinis a bone morphogenetic protein (BMP). Such compositions are useful forfracture healing and repair. These compositions may be used forincreasing bone mineral density. Osteoporotic or osteopenic bone isoften characterized by suboptimal bone density and therefore thecompositions and methods may be used for for increasing bone mineraldensity and treating osteoporosis. The methods and compositions mayincrease bone mass density and minimize or reduce the incidence ofosteoporosis- related fractures. The methods comprise administering aninjectable formulation of a DNA sequence encoding an osteogenic proteinsuitable for systemic administration in an amount effective for fracturerepair. The compositions may be administered in admixture with apharmaceutically acceptable vehicle.

In a preferred embodiment, the invention features a composition andmethod for promoting fracture repair wherein the composition comprises aDNA sequence encoding BMP-6 and is employed in a method involvingsystemic administration to a patient in need of fracture repair. In afurther preferred embodiment the BMP DNA sequence is contained on anadenovirus vector.

In other embodiments the following BMPs may be suitable:BMP-2, BMP-3,BMP-4, BMP-5, BMP-6 and BMP-7, BMP-10, BMP-12 and BMP-13, BMP-15,BMP-16, further described below.

The invention further provides methods and compositions for promotingosteogenesis wherein the composition comprises an osteogenic protein. Inpreferred embodiments the osteogenic protein is a bone morphogeneticprotein (BMP). Such compositions are useful for fracture healing andrepair. These compositions may be used for increasing bone mineraldensity. Osteoporotic or osteopenic bone is often characterized bysuboptimal bone density and therefore the compositions and methods maybe used for for increasing bone mineral density and treatingosteoporosis. The composition and method therefore as an injectableagent would be useful in fracture prevention and treatment withoutsurgical intervention. The composition and method would decrease theoccurance and/or severity of fracture to osteoporotic bone.

In a preferred embodiment, the invention features a composition andmethod for promoting fracture repair wherein the composition comprisesBMP-6 and is employed in a method involving systemic administration to apatient in need of fracture repair.

In other embodiments the following BMPs may be suitable: BMP-2, BMP-3,BMP4, BMP-5, BMP-6 and BMP-7, BMP-10, BMP-12 and BMP-13, BMP-15, BMP-16,further described below.

The sequences encoding osteogenic proteins as well as the proteins arepreferably selected from the family of proteins known as thetransforming growth factors-beta (TGF-β) superfamily of proteins, whichincludes the bone morphogenetic proteins (BMPs), activins and inhibins.Most preferably, the active agent includes at least one protein selectedfrom the subclass of proteins known generally as BMPs, which have beendisclosed to have osteogenic activity, and other growth anddifferentiation type activities. These BMPs include BMP proteins BMP-2,BMP-3, BMP-4, BMP-5, and BMP-7, BMP-10, BMP-12 and BMP-13, BMP-15,BMP-16, further described below. The osteogenic agent is most preferablythe DNA sequences encoding BMP-6 or BMP-6 proteins or peptides. The DNAand protein sequence and methods for producing BMP-6 are disclosed inU.S. Pat. Nos. 5,187,076, 5,459,047 and 5,849,880 and in U.S. Ser. No.09/189,157, the disclosures of which are herein incorporated byreference. Other agents and the DNA sequences encoding them which arecapable of inducing bone growth or fracture repair or increasing theformation of bone tissue may also be utilized.

Among the DNA molecules and proteins useful in the present invention arethose comprising the coding sequences for one or more of the BMPproteins BMP-2, BMP-3, BMP-4, BMP-5, BMP-6 and BMP-7, disclosed forinstance in U.S. Pat. Nos. 5,108,922; 5,013,649; 5,116,738; 5,106,748;5,187,076; and 5,141,905; BMP-8, disclosed in PCT publicationWO91/18098; and BMP-9, disclosed in PCT publication WO93/00432, BMP-10,disclosed in PCT application WO94/26893; BMP-11, disclosed in PCTapplication WO94/26892, or BMP-12 or BMP-13, disclosed in PCTapplication WO95/16035, or BMP-15, disclosed in PCT applicationWO96/36710 or BMP-16, disclosed in co-pending patent application Ser.No. 08/715/202, filed Sep. 18, 1996.

Other DNA molecules which may also be useful include those encodingVgr-2, and any of the growth and differentiation factors [GDFs],including those described in PCT applications WO94/15965; WO94/15949;WO95/01801; WO95/01802; WO94/21681; WO94/15966; and others. Also usefulin the present invention may be BIP, disclosed in WO94/01557; and MP52,disclosed in PCT application WO93/16099. The disclosures of all of theabove applications are hereby incorporated by reference for thedisclosure contained therein.

Other DNA molecules which may be useful, in addition to DNA encoding aBMP protein, include DNA molecules encoding other therapeutically usefulagents including growth factors such as epidermal growth factor (EGF),fibroblast growth factor (FGF), transforming growth factor (TGF-α andTGF-β), hedgehog proteins such as sonic, indian and desert hedgehog,parathyroid hormone and parathyroid hormone related peptide, cadherins,activins, inhibins, and IGF, FSH, frizzled, frzb or frazzled proteins,PDGF and other endothelial growth factors, BMP binding proteins such aschordin and fetuin, estrogen and other steroids as well as truncatedversions thereof, and transcription factors such as wnt proteins, madgenes and cbfa.

In the present invention, the vectors used for incorporation andexpression of the DNA are preferably viral in origin, particularlyadenoviruses, as well as retroviruses. Adenoviruses are advantageous inthat they do not require cells in the state of proliferation, and have ahigh efficiency rate of infection both in vitro and in vivo, whereasretroviruses are more often suitable for in vitro infection.Adenoviruses also offer high levels of transgene expression and theability to achieve high titers. These advantages make adenoviruses moresuitable for primary cells, cell lines and direct in vivo transduction.In addition, expression of the transgene is transient and the adenoviralvector does not integrate into the cell genome, making the vectors saferfor use. All generations of recombinant adenoviruses are suitable,including the present generation, (E1 deleted), and new generationswhich have reduced antigenicity (E1 , E3, E4 deleted viruses, or E1, E4deleted and E3 overexpressed). Smith (1995); Dunbar (1996); Roemer(1992); Graham (1991); Kozarsky (1993); and Ilan (1997). The disclosureof each of the above publications is hereby incorporated by referencefor the contents thereof.

The expression of the genes which are expressed in the present inventionmay be constitutive or controlled. Controlling the expression can beachieved by external control by means of regulatory elements, such aswith an inducibly controlled promoter, for example, a tetracyclinecontrolled promoter, as further described herein, or by using regulatoryelements from tissue specific or temporally specific genes to direct theexpression only to certain specified differentiation pathways or atcertain stages in differentiation. For example, the osteocalcin promotermay be used for induction at late stages of bone formation andcalcification.

The DNA sequences encoding BMP proteins useful in the present invention,as disclosed in the referenced applications and patents cited above,also include the disclosed DNA sequences, free of association with DNAsequences encoding other proteinaceous materials, and coding onexpression for the proteins of the invention. These DNA sequencesinclude those depicted in Tables II and III in a 5′ to 3′ direction orportions thereof. Further included are those sequences which hybridizeunder stringent hybridization conditions [see, T. Maniatis et al,Molecular Cloning (A Laboratory Manual), Cold Spring Harbor Laboratory(1982), pages 387 to 389] to the particular DNA sequence and demonstratecartilage and/or bone formation activity. Such cartilage and/or boneformation activity may be in the rat bone formation assay. An example ofone such stringent hybridization condition is hybridization at 4×SSC at65° C., followed by a washing in 0.1×SCC at 65° C. for an hour.Alternatively, an exemplary stringent hybridization condition is in 50%formamide, 4×SCC at 42° C.

Similarly, DNA sequences which encode proteins similar to the proteinencoded by the disclosed sequence, but which differ in codon sequencedue to the degeneracies of the genetic code or allelic variations(naturally-occurring base changes in the species population which may ormay not result in an amino acid change) also encode the proteins of theinvention described herein. Variations in the DNA sequences which arecaused by point mutations or by induced modifications (includinginsertion, deletion, and substitution) to enhance the activity,half-life or production of the polypeptides encoded thereby are alsoencompassed in the invention.

Similarly, the proteins provided herein also include factors encoded bythe sequences similar to those of naturally-occurring BMP relatedproteins, such as BMP-6, but into which modifications are naturallyprovided (e.g. allelic variations in the nucleotide sequence which mayresult in amino acid changes in the polypeptide) or deliberatelyengineered. For example, synthetic polypeptides may wholly or partiallyduplicate continuous sequences of the amino acid residues of theparticular BMP. These sequences, by virtue of sharing primary,secondary, or tertiary structural and conformational characteristicswith bone inductive polypeptides of naturally-occurring BMP s maypossess biological properties in common therewith.

In further embodiments, compositions and methods of the presentinvention may comprise, in addition to the DNA sequences encoding, forexample a BMP protein, A DNA sequence encoding additional proteins, suchas additional members of the TGF-β superfamily of proteins, describedabove.

These compositions and methods may be used to promote osteogenesis andin fracture repair. The compositions and methods may also be useful inincreasing bone mass density.

In one embodiment of the invention, wherein it is the protein which issystemically administered such protein can be modified for systemicadministration. Such modification can include chemical modification byprocedures and methods known to those skilled in the art.

In another embodiment the protein can be modified or otherwiseformulated for controlled release. In such a composition, the BMPprotein is preferably encapsulated, or otherwise administered in amanner which allows for example, slow release over a sustained period oftime. For example, the BMP component may be encapsulated in a resorbablepolymer delivery system, such as polylactic acid, polyglycolic acid orcopolymers thereof, polyorthoesters, polyorthocarbonates, and otherpolymers. Suitable polymers are disclosed for example in EP 0145240, thedisclosure of which is hereby incorporated by reference.

It is expected that osteogenic proteins may act in concert with orperhaps synergistically with other related proteins and growth factors.Therefore, further therapeutic methods and compositions of the inventiontherefore comprise a therapeutic amount of a sequence encoding anosteogenic protein or an osteogenic protein or peptide with atherapeutic amount of at least one of the BMP proteins described above.Such compositions may comprise separate molecules of the BMP proteins orheteromolecules comprised of different BMP moieties.

Compositions and methods of the present invention may be combined withother agents beneficial to the treatment of the defect, wound, or tissuein question.

In the present invention, the vectors used for incorporation andexpression of the DNA are preferably viral in origin, particularlyadenoviruses, as well as retroviruses. Adenoviruses are advantageous inthat they do not require cells in the state of proliferation, and have ahigh efficiency rate of infection both in vitro and in vivo, whereasretroviruses are more often suitable for in vitro infection.Adenoviruses also offer high levels of transgene expression and theability to achieve high titers. These advantages make adenoviruses moresuitable for primary cells, cell lines and direct in vivo transduction.In addition, expression of the transgene is transient and the adenoviralvector does not integrate into the cell genome, making the vectors saferfor use. All generations of recombinant adenoviruses are suitable,including the present generation, (E1 deleted), and new generationswhich have reduced antigenicity (E1, E3, E4 deleted viruses, or E1, E4deleted and E3 overexpressed). Smith (1995); Dunbar (1996); Roemer(1992); Graham (1991); Kozarsky (1993); and Ilan (1997). The disclosureof each of the above publications is hereby incorporated by referencefor the contents thereof.

The expression of the genes which are expressed in the present inventionmay be constitutive or controlled. Controlling the expression can beachieved by external control by means of regulatory elements, such aswith an inducibly controlled promoter, for example, a tetracyclinecontrolled promoter, as further described herein, or by using regulatoryelements from tissue specific or temporally specific genes to direct theexpression only to certain specified differentiation pathways or atcertain stages in differentiation. For example, the osteocalcin promotermay be used for induction at late stages of bone formation andcalcification.

The therapeutic method includes administering the compositionsystemically as an injectable. In certain embodiments the methodinvolves local injection. The composition may further involve an implantor device. When administered, the therapeutic composition for use inthis invention is, of course, in a pyrogen-free, physiologicallyacceptable form. Further, the composition may desirably be encapsulatedor injected in a viscous form for delivery to the site of tissue damage.Therapeutically useful agents which may also optionally be included inthe composition as described above, may alternatively or additionally,be administered simultaneously or sequentially with the composition inthe methods of the invention. In addition, the compositions of thepresent invention may be used in conjunction with presently availabletreatments.

In embodiments for example for treatment of osteoporotic conditions,materials which may be useful as the carrier in practicing the presentinvention include pharmaceutically acceptable materials having viscosityand polarity such that, when added to the bone morphogenetic protein,form a composition that possesses appropriate handling characteristicsfor injectable application to the site of osteoporotic or osteopenicbone. Adding the carrier to the bone morphogenetic protein allows theprotein to remain in the diseased or lesioned site for a time sufficientto allow the protein to increase the otherwise natural rate ofregenerative osteogenic activity of the infiltrating mammalianprogenitor or other cells, and to form a space in which new tissue cangrow and allow for ingrowth of cells. The carrier may also allow thebone morphogenetic protein to be released from the disease or lesionsite over a time interval appropriate for optimally increasing the rateof regenerative osteogenic activity of the progenitor cells. The carriermay also supply a framework on which to induce new formation in severelyosteoporotic bone.

The most preferred family of carriers comprises collagenous materials.These are preferably in a form suitable for injection, such as a gel.Such gels may be cross-linked or non-cross-linked. Other forms ofcollagen, such as dispersions or fibrillar collagen, may also be usefulin the methods of the present invention. Another preferred family ofcarriers is cellulosic materials such as alkylcellulose, includinghydroxyalkylcellulose, methylcellulose, ethylcellulose,hydroxyethylcellulose, hydroxypropylcellulose,hydroxypropylmethylcellulose, and carboxymethylcellulose, the mostpreferred being the cationic salts of carboxymethylcellulose (CMC).

In the case of cellulosic carriers and collagen gels, it is preferredthat the carrier be in the form of a hydrated cellulosic viscous gel.Viscosity may be increased through mechanical means, such as highagitation for a suitable period of time, followed by autoclaving, orchemically. The active agent and cellulosic carrier is preferably in asolution of suitable buffer. One preferred buffer solution is acomposition comprising, in addition to the active agent, about 1.0 toabout 10.0% (w/v) glycine, about 0.1 to about 5.0% (w/v) of a sugar,preferably sucrose, about 1 to about 20 mM glutamic acid hydrochloride,and optionally about 0.01 to about 0.1% of a non-ionic surfactant, suchas polysorbate 80. Preferred solutions are from about 1% to about 20%w/v cellulosic carrier/buffer. If desired, a salt may be added. Apreferred viscous gel carrier is described in Example 2 below. Theamount of osteogenic protein useful with viscous gel carrier isgenerally in a range of from about 0.1 to about 100 mg, preferably about1 to about 100 mg; most preferably about 10 to about 80 mg per cubiccentimeter of implant material required.

Another class of materials of particular interest for injectablecarriers are resorbable hydroxyapatites as well as minerals, ceramicsand phosphates. Resorbable hydroxyapatites, for example, can beformulated at various porosities with varying resorption rates; theirhandling characteristics vary from hard implantable types, to gel-likeconsistency, to those that are injectable but harden at bodytemperature. Suitable hydroxyapatite and ceramic carriers are described,for example in WO96/36562; and U.S. Pat. Nos. 5,543,019; 5,306,305;5,258,044; 5,496,399; 5,455,231; 5,336,264; 5,178,845; 5,053,212;5,047,031; 5,129,905; 5,034,059; 4,880,610; 5,290,763; and 5,563,124;the disclosures of which are incorporated herein by reference.

Another preferred family of carriers for administration of the activeagent of the present invention are injectable polymers, which may beviscous and which may optionally include a sequestering agent as well.Suitable polymers and sequestering agents include those described inU.S. Pat. No. 5,171,579, the entire disclosure of which is incorporatedherein by reference. Other polymers include the pluronics, such asPoloxamer 407 gel. Pluronics are a class of water soluble ABA type blocksurfactant copolymers which exhibit the unique property of reversethermal gelation. They are liquid (and hence syringeable) at 4° C. andgel at body temperature. Poloxamer 407, MW 12,500, is excreted unchangedin the urine after systemic absorption and has supposedly been shown tobe non-toxic in animals. Polylactides and/or polyethylene glycols,including poly(lactide)/poly(ethylene glycol) gels. Polylactides may bedissolved in polyethylene glycols, such as low molecular weight (2000)PLA dissolved in PEG to produce a syringeable solution that precipitatesPLA upon injection into an aqueous environment, resulting in arelatively firm gel. In addition, the literature cites conjugates, suchas Poly(lactic acid)-poly(ethylene glycol) conjugates, as appropriatecarriers for BMPs (Miyamoto et al., Clin. Orthop. Rel. Res. 294:333(1993)). Among the materials useful as sequestering agents arehyaluronic acid, sodium alginate, poly(ethylene glycol), polyoxyethyleneoxide, carboxyvinyl polymer and poly(vinyl alcohol), and cellulosicmaterials, such as hydroxycelluloses. One such preferred agent iscarboxymethylcellulose.

The above materials disclosed to be useful as sequestering agents maythemselves be useful as carriers for injection. In addition,combinations of the above described materials may be used.

In cases where the carrier may be of higher viscosity than optimal, thecarrier may optionally be combined with a diluent, such as aqueousglycerol, preferably the carrier diluent would be present inconcentrations of about 10 to about 80% (v/v). Also, the above materialsmay be combined in particular embodiments of the present invention. Forexample, polymers, such as porous particulate polymers, may be dissolvedor suspended in cellulosic or gel carriers to increase viscosity.

In a preferred embodiment of the present invention, the active agentsare administered locally through injection using only a suitable bufferas carrier. One suitable buffer comprises glycine, sucrose, and glutamicacid hydrochloride, at a pH of less than 6.0. Preferred compositions ofbuffer solutions comprise about 1.0 to about 10.0% (w/v) glycine, about0.1 to about 5.0% (w/v) of a sugar, preferably sucrose, about 1 to about20 mM glutamine, glutamic acid, or glutamic acid hydrochloride, andoptionally about 0.01 to about 0.1% of a non-ionic surfactant, such aspolysorbate 80. In a preferred embodiment of the invention, thisformulation comprises about 2.5% glycine (g/100 ml (w/v)), about 0.5%sucrose (w/v), about 5 mM glutamic acid hydrochloride (about 0.1% w/v),and about 0.01% (w/v) polysorbate 80, at a pH of about 4.5. This bufferhas been described as MFR 842. Further buffers suitable for use in thepresent invention are described in U.S. Pat. No. 5,385,887, thedisclosure of which is hereby incorporated by reference. Preferredsolutions may also include combinations of buffer and other carrier,such as a combination of buffer and cellulosic carrier. Preferred rangesfor this combination are from about 1% to about 20% w/v cellulosiccarrier/buffer. If desired, a salt may be added.

In certain embodiments, the compositions may include an appropriatematrix and/or sequestering agent as a carrier. For instance, the matrixmay support the composition or provide a surface for cartilaginousand/or bone tissue formation and/or other tissue formation. The matrixmay provide slow release of the protein and/or the appropriateenvironment for presentation thereof. The sequestering agent may be asubstance which aids in ease of administration through injection orother means, or may slow the migration of protein from the site ofapplication.

In some embodiments, genetically engineered cells may be administered incombination with an appropriate matrix, for instance, for supporting thecomposition and providing a surface for bone, cartilage, and/or otherconnective tissue growth. The matrix may be in the form of traditionalmatrix biomaterials. The matrix may provide slow release of theexpressed protein and differentiated cells and/or the appropriateenvironment for presentation thereof. In some embodiments, variouscollagenous and non-collagenous proteins are expected to be upregulatedand secreted from the pluripotent stem cells. This phenomenonaccelerates tissue regeneration by enhancing matrix deposition. Matrixproteins can also be expressed in the genetically engineered cells andenhance the engraftment and attachment of transplanted cells into thetransplant area.

The choice of a carrier material is based on biocompatibility,biodegradability, mechanical properties, cosmetic appearance andinterface properties. The particular application of the compositionswill define the appropriate formulation. Potential matrices for thecompositions may be biodegradable and chemically defined. Furthermatrices are comprised of pure proteins or extracellular matrixcomponents. Other potential matrices are non-biodegradable andchemically defined. Preferred matrices include collagen-based materials,including sponges, such as Helistat⁷ (Integra LifeSciences, Plainsboro,N.J.), or collagen in an injectable form, as well as sequesteringagents, which may be biodegradable, for example hyaluronic acid derived.Biodegradable materials, such as cellulose films, or surgical meshes,may also serve as matrices. Such materials could be sutured into aninjury site, or wrapped around the cartilage.

Another preferred class of carrier are polymeric matrices, includingpolymers of poly(lactic acid), poly(glycolic acid) and copolymers oflactic acid and glycolic acid. These matrices may be in the form of asponge, or in the form of porous particles, and may also include asequestering agent. Suitable polymer matrices are described, forexample, in WO93/00050, the disclosure of which is incorporated hereinby reference.

Preferred families of sequestering agents include blood, fibrin clotand/or cellulosic materials such as alkylcelluloses (includinghydroxyalkylcelluloses), including methylcellulose, ethylcellulose,hydroxyethylcellulose, hydroxypropylcellulose,hydroxypropyl-methylcellulose, and carboxymethylcellulose, the mostpreferred being cationic salts of carboxymethylcellulose (CMC). Otherpreferred sequestering agents include hyaluronic acid, sodium alginate,poly(ethylene glycol), polyoxyethylene oxide, carboxyvinyl polymer andpoly(vinyl alcohol). The amount of sequestering agent useful herein is0.5-20 wt %, preferably 1-10 wt % based on total formulation weight,which represents the amount necessary to prevent desorbtion of theprotein from the polymer matrix and to provide appropriate handling ofthe composition, yet not so much that the progenitor cells are preventedfrom infiltrating the matrix, thereby providing the protein theopportunity to assist the activity of the progenitor cells.

Additional optional components useful in the practice of the subjectapplication include, e.g. cryogenic protectors such as mannitol,sucrose, lactose, glucose, or glycine (to protect the protein fromdegradation during lyophilization), antimicrobial preservatives such asmethyl and propyl parabens and benzyl alcohol; antioxidants such asEDTA, citrate and BHT (butylated hydroxytoluene); and surfactants suchas poly(sorbates) and poly(oxyethylenes).

The identification of patients needing treatment for various conditionsincluding osteoporotic or osteopenic conditions may be accomplished byprocedures which are well known in the art. These procedures includemeasurement of bone mass/density using dual-energy X-ray absorptiometry(DEXA), Kilgus et al., J. Bone & Joint Surgery, 75-B:279-287 (1992);Markel et al., Acta Orthop Scand, 61:487498 (1990); and quantitativecomputed tomography (QCT), Laval-Jeantet et al., J Comput Assist Tomoqr,17:915-921 (1993); Markel, Calcif Tissue Int, 49:427-432 (1991);single-photon absorptiometry, Markel et al. Calcif Tissue Int,48:392-399 (1991); ultrasound transmission velocity (UTV); Heaney etal., JAMA, 261:2986-2990 (1989); Langton et al., Clin Phys Physiol Meas,11:243-249 (1990); and radiographic assessment, Gluer et al., J Bone &Mineral Res, 9:671-677 (1994). Other methods of identification ofpatients at risk of bone fracture include assessment of age-relatedfactors, such as cognisance, as well as prior occurrence ofosteoporosis-related fractures. Porter et al., BMJ, 301: 638-641 (1990);Hui et al., J Clin Invest, 81:1804-1809 (1988). The above publicationsare hereby incorporated by reference herein.

The dosage regimen will be determined by the attending physicianconsidering various factors which modify the action of the composition,e.g., amount of tissue desired to be formed, the site of tissue damage,the condition of the damaged tissue, the size of a wound, type ofdamaged tissue, the patient's age, sex, and diet, the severity of anyinfection, time of administration and other clinical factors. The dosagemay vary with the type of vehicle carrier or matrix used in thereconstitution and the types of additional proteins or DNA sequences inthe composition. The addition of other known growth factors to the finalcomposition, may also affect the dosage.

The preparation and formulation of such physiologically acceptablenucleic or protein compositions, having due regard to pH, isotonicity,stability and the like, is within the skill of the art. The therapeuticcompositions are also presently valuable for veterinary applications dueto the lack of species specificity in TGF-β proteins. Particularlydomestic animals and thoroughbred horses in addition to humans aredesired patients for such treatment with the compositions of the presentinvention.

Progress can be monitored by periodic assessment of tissue formationgrowth and/or repair. The progress can be monitored by methods known inthe art, for example, X-rays, arthroscopy, histomorphometricdeterminations and tetracycline labeling and various methods set forthin the examples below.

The invention, in certain of its embodiments, is illustrated by theexamples below. These examples are not limiting. As will be appreciatedby those skilled in the art, many variations and combinations of thefollowing examples are available. These combinations and variationsconstitute a part of the present invention.

EXAMPLE I Systemic Administration of BMP-6 A. BMP-6 Adenoviral Vectors

The full length BMP-6 clone defines a 1539 base-pair open readinf framethat encodes the 513-amino acid hBMP-6. The human BMP-6 cDNA wasisolated as a SalI fragment from the BMP-6EMC vector, and the ends werefilled in with Vent Polymerase (New England Biolabs, Beverly, Mass.).The Adori 1-1 BMP-6 vector was created with the insertion of the BMP-6cDNA into the EcoRV restriction site of the adenovirus vector Adori 1-1.The final construct was verified by extensive restriction mapping andfull-length sequencing of the BMP-6 insert. The Adori 1-1 EGFP (enhancedgreen fluorescence protein) vector was derived from a digest of pEGFP-N1(CLONTECH Laboratories, Inc., Palo Alto, Calif.) with EcoR1 and Not1 andthe EGFP cDNA was inserted between the EcoR1 and Not1 sites of Adori1-1. The Adori 1-1 EGFP construct was confirmed by restriction mappingand 5′-end sequencing. Expression of hBMP-6 and GFP mRNA transcripts isdriven from the cytomegalovirus (CMV) immediate early promoter andenhancer sequence. The expression cassette is located downstream of theSV40 origin and enhancer, and 0-1 map units of the adenovirus type5(Ad5). The SV40 splice donor and acceptor sequence is located betweenthe CMV promoter and the cDNA. Following the insert is a SV40 poly Asite, 9-16 map units of Ad5, and the puc 19 origin.

Replication-defective, E1 and E3 minus, type 5 (del327) recombinantadenovirus was generated by homologous recombination in human embryonickidney 293 cells (ATCC, Rockville, Md.). Virus was generated bycotransfection of Adori expression plasmids, described above, and 9 to36 map units of adenovirus backbone. Recombinant adenovirus wasamplified and released from 293 cells by three cycles of freeze thawing.The virus was further purified by centrifugation through two cesiumchloride gradients and dialyzed to equilibrium against phosphatebuffered saline, pH 7.2 at 4° C. Following dialysis, glycerol was addedto a final concentration of 10% and the virus was stored at −80° C.until use. Virus concentration, expressed in particles/ml, wasdetermined by measuring the optical density at 260 nm. Endotoxin levelswere measured with the use of a Limulus Amebocyte Lysate kit(BioWhittaker, Walkersville, Md.). The virus was further characterizedby PCR amplification of the insert using vector specific primers:

-   Forward Primer: 5′-TGGATGTTGCCTTTACTTCTA-3′-   Reverse Primer: 5′-TTCACTGCATTCTAGTTGTG-3′ or BMP-6 specific    primers:-   Forward Primer: 5′-TGTGMCCTGGTGGAGTACG-3′-   Reverse Primer: 5′-MGMCCGAGATGGCATTTAGC-3′

PCR products were sequenced to confirm the integrity of the insert.Expression of the transgene and secretion of mature BMP-6 were confirmedby metabolic labeling of 293 cells and immunoprecipitation with a BMP-6selective monoclonal antibody.

B. Closed-Femur Fracture Model

C57BL/6 male mice (Jackson Lab.) between the ages of 12 and 16 weekswere anesthetized with Pentobarbital (60 mg/kg, IP). A sterile ocularointment was applied to both eyes for protection. The upper-right hindlimb was shaved down to the skin and the exposed skin was scrubbedsequentially with an ethanol and Duraprep pads.

After surgical preparations, mice were placed in a sterile surgicalfield. A 5-10 mm incision was created dorsal to the femoral head. A 25gauge, 1 inch needle was inserted through the trochanteric fossa andpushed down the marrow canal to the distal femur. After needleinsertion, the needle was cut just below the skin. The incision wasclosed with the use of Nexaband surgical glue. Mice were monitoredduring the surgical procedure to maintain anesthesia and bodytemperature.

Closed femur fractures were created in a manner similar to thatdescribed by Bonnarens and Einhorn (J. Orthop. Res. 2:97-101, 1984.).The fracture apparatus is shown in FIG. 1.

The pre-pinned, right leg of a mouse was securely positioned such thatthe middle of the femur rested between the two-pronged animal supportstage and the blunt blade. A 150 gram weight was raised to a height of7.5 cm and then dropped onto the spring below. The fracture apparatuswas adjusted so that the impact displacement of the blunt blade towardsthe femur was about 1 mm.

Each mouse was removed from the fracture apparatus after a single impacttrauma and subjected to radiographic analysis with the use of a digitalcamera x-ray cabinet (Faxitron X-Ray Corporation; MX-20). Animals wereradiographed to assess both the placement of the intramedullary pin andthe quality of the fracture. Pin placement was judged successful if: I)surgical insertion did not exceed five minutes per mouse or necessitateexcessive animal manipulation; ii) pin was placed in middle of medullarycanal; and iii) pin was not bent or sticking into another part of thefemur. Fractures were judged successful if: I) fracture occuredmid-femur; ii) fracture was transverse and not comminuted. Animals thatdid not meet these criteria were euthanized immediately.

Mice which met the radiographic criteria were allowed to recover on awarming blanket, while being monitored.

C. Effect of Adenoviral Constructs on Fracture Repair

Mice with femur fractures were randomly assigned to two groups beforethey recovered from surgical anesthesia. Mice in group 1 received a 50ul injection of adenovirus-GFP in the tail vein. Mice in group 2received a 50 ul injection of adenovirus-BMP-6 in the tail vein. Thenumber of viral particles administered to each animal was 5×10¹⁰particles/injection. Mice were monitored twice a day before scheduledeuthanasia on days 5, 7 and 10. At the scheduled times, mice wereeuthanized and subjected to radiographic analysis to assess pinplacement and fracture quality. Animals in which the fracture did notappear to be stabilized by the pin were discarded from the study. Theright legs of the remaining mice were removed. Intramedullary pins werenot removed at this time and the legs (minus the skin and hair) werefixed in a solution of 10% neutral-buffered formalin (Hydrol ChemicalCo., Yeadon, Pa.).

D. Histological Analysis of Fractured Femurs

Tissues were sectioned and stained with hematoxylin and eosin.

Day 5

A representative femur from each of the two groups showed the beginningsof a fracture repair process. The repair process was manifested by areason the section (at 2× magnification) of periosteal cell proliferationadjacent to the fracture. At a higher magnification (20×), areas ofactive chondrogenesis, as determined by the presence of hypertrophicchondrocytes, were readily apparent in a femur from the BMP-6 group. Incontrast, hypertrophic chondrocytes were not readily detected in areasadjacent to the fracture from the GFP group. There were no well definedexternal calluses at day 5 in either group.

Day 7

There was no well defined external callus around the area of thefracture in a femur from the GFP group. This section appeared similar tothe GFP femur from day 5. In contrast, there was an obvious andwell-defined external callus around the fractured bone from the BMP-6group.

Day 10

There was no well defined external callus around the area of thefracture in a femur from the GFP group. At low magnification, thissection appeared similar to the GFP-femurs from days 5 and 7. However,at higher magnification, it was possible to see that limited numbers ofperiosteal cells, adjacent to the fracture, were hypertrophicchondrocytes. In contrast, there was an obvious and well-definedexternal callus around the fractured bone from the BMP-6 group. Thiscallus had evidence of bone formation and neo-vascularization.

Other areas of bone were damaged during the creation of the fracture.For example, the femoral head was punctured during the process of pininsertion. These additional areas of damaged bone also showed obvioussigns of a bone repair/formation process in femurs from the BMP-6 group,but not from the GFP group.

The histological data demonstrates that systemic BMP-6, primarilysecreted from hepatocytes, is capable of accelerating fracture repair.

Example II A. Ectopic Formation of Bone

Several independent experiments were performed to assess the osteogeniceffects of the hBMP-6 adenoviral vector. In these experiments, femaleC57BI/6 SCID or immunocompetent mice were injected intramuscularly, intoboth quadriceps muscles, with a single dose of adenovirus encodinghBMP-6 or GFP (1 to 2.5×10¹⁰ particles/injection). Mice from eachexperimental group were sacrificed at various (usually one or two) timepoints post injection. Tissues were harvested, fixed in formalin, andstained with hematoxylin and eosin for histopathology. In allexperiments, hBMP-6 induced endochondral bone formation in musclesderived from immunocompromised and to a lesser extent in immunocompetentmice. The following describes results obtained from an experiment inwhich immunocompromised mice were used and tissues were collected atfive time points post injection.

C57BL/6 SCID female mice (Jackson Lab.) were divided into two groups tostudy the bone-anabolic effects of hBMP-6. All mice were brieflyanaesthetized with the inhalation of isoflurane. Anesthesia was followedby the intramuscular injection of either adenovirus-GFP oradenovirusBBMP-6 into both quadriceps muscles of each mouse. Eachquadriceps muscle was injected with 1.25×10¹⁰ virus particles in avolume of 25 microliters. Mice were housed five to a cage on a standarddiet of food and water and groups of animals were euthanized on days 2,3, 4, 7 and 14. Both quadriceps muscles were dissected and removed fromthe animals and fixed in a solution of 10% neutral-buffered formalin(Hydrol Chemical Co., Yeadon, Pa.). The day 14 mice were subjected tox-ray analysis with the use of a digital camera x-ray cabinet (FaxitronX-Ray Corporation; MX-20). This group of animals was radiographed toassess the formation of ectopic bone in the quadriceps muscles.

Selected muscle samples were set aside and total RNA was isolated withthe use of the RNAgents and RNeasy kits (Promega and Qiagen,respectively). The RNAgents kit was used as recommended by themanufacturer up to and including RNA precipitation with the use ofisopropanol. Isopropanol was washed from the RNA pellet with the use ofa 75% ethanol solution. Total RNA was collected with the use of amicro-centrifuge and the pellet was dissolved in lysis buffer from theRNeasy kit. RNA purification was performed as recommended by themanufacturer. Total RNA was eluted in water and the concentrationdetermined with the use of a spectrophotometer.

The RT-PCR was used to measure relative levels of GFP and BMP-6. RT-PCRwas performed with the use of an ABI PRISM 7700 Sequence DetectionSystem (Applied Biosystems). Primers and probes relied upon a nucleotidesequence, located within the SV40 poly A sequence, common to both GFPand BMP-6 adenoviral constructs. The primers and probes used were asfollows:

-   Forward Primer: 5′-GACATGATAAGATACATTGATGAGTTTGG-3′-   Reverse Primer: 5′-GCAATAGCATCACAAATTTCACAAAT-3′-   Taqman Probe: 5′-CAAACCACAACTAGMTGCAGTGAAAAMATGCTT-3′

Before the RT-PCR was performed, all total RNA samples were subjected totreatment with RNase-free DNase to remove trace amounts of genomic DNA.The Taqman EZ RT-PCR CORE REAGENTS kit (Perkin Elmer) was used inaccordance with the manufacturer's instructions. The PCR took place in50 ul solutions that contained 50 ng of total RNA and 5 uM of probe andprimers. The PCR conditions were as follows:

-   Stage 1: 50° C. for 2 min.    -   -   60° C. for 30 min.

    -   Stage 2: 95° C. for 5 min.

    -   Stage 3: 95° C. for 15 sec. X40        -   60° C. for 1 min.

This analysis demonstrated the local expression of mRNA for GFP andBMP-6 in quadriceps muscles.

D. Histological Analysis of Quadriceps Muscles

Tissues were sectioned and stained with hematoxylin and eosin.

Injection of adenovirus-GFP did not lead to the formation of ectopicbone in muscle as assessed by visual inspection of the muscle, x-rayradiographs and histology. Histological analysis of the tissue sectionsrevealed acute and subacute inflammation which was characterized byneutrophil, lymphocyte and macrophage infiltration. This cellularinfiltration was detected as early as day 2, appeared to peak on days 4and 7 and appeared to be resolved on day 14. In addition to cellularinfiltration, there was also evidence of edema and skeletal muscle fiberdegeneration on days 3 and 4 and muscle fiber regeneration on days 7 and14.

Injection of adenovirus-BMP-6 did lead to the formation of ectopic bonein muscle as assessed by visual inspection of the muscle, x-rayradiographs and histology. It was possible to detect an increase in thesize of the muscle as early as day 4 after the injection. X-ray imagesshowed the presence of radio-opaque masses in the muscles of the day 14animals. Histological analysis of the tissue sections revealed acuteinflammation on days 2 and 3. Mesenchymal cell proliferation wasobserved on days 4,7 and 14. Cartilaginous tissue was evident on days 7and 14 and marked bone formation was clearly identified on day 14.

These data demonstrate that intramuscular administration ofadenovirus-BMP-6 results in endochondral bone formation.

Example III Adenovirus/BMP-6 Accelerates Osteotomy Healing in a RabbitUlna Model

The rabbit ulna model was used to determine if percutaneous injection ofadenovirus containing BMP-6 cDNA could be used to accelerate osteotomyhealing. This model has been used as a screening model to demonstrateacceleration of osteotomy healing in response to surgical implantationof the rhBMP-2 on a collagen sponge and in a calcium phosphate carrier.

A. Methods

Bilateral mid-diaphyseal ulna 1-2 mm osteotomies were created in 18adult male rabbits. One following surgery, 200 ml containing 1×10¹²adenovirus/BMP-6 particles was injected percutaneously into an osteotomyin 12 animals. A similar volume containing the same number ofadenovirus/GFP particles was injected into an osteotomy in the remaining6 animals. The adenvirus/GFP animals served as controls for the effectof administering adenovirus without BMP-6 cDNA. In both groups thecontralateral osteotomy served as an untreated surgical control.Intra-muscular injections of adenvirus/GFP were also administered in anumber of the animals to validate the efficacy of the viral vectorsystem to express the delivered cDNA. Six of the animals in theadenovirus/BMP-6 group were euthanized at 6 weeks and 8 weeks aftersurgery. The animals in the adenvirus/GFP group were euthanized 6 weeksafter surgery. Outcome measures included serial radiography, torsionalbiomechanics, histology and GFP expression.

B. Results

Histologic evaluation of the intramuscular adenovirus/GFP injectionsverified that there was cDNA expression following viral injection.Serial radiographs revealed the presence of mineralized callus as earlyas two weeks after injection of the adenovirus/BMP-6 (3 weeks aftercreating the osteotomy). At 6 weeks after creating the osteotomy therewas bridging mineralized callus across the osteotomy site in all of theadenvirus/BMP-6 injected animals. The osteotomy was bridged and theosteotomy was no longer visible in the adenovirus/BMP-6 limbs at 8 weeksafter creating the osteotomy. The appearance of mineralized bone andbridging callus was delayed in the surgical control osteotomies and theosteotomies injected with adenovirus/GFP. All of the surgical controland adenvirus/GFP injected limbs had visable osteotomy lines at 8 weeks.

Maximum torsional strength and stiffness osteotomies were greater in theadenovirus/BMP-6 limbs compared to the contralateral surgical controllimbs at both 6 and 8 weeks after creating the osteotomy (Table 1 and2). Maximum torsional strength and stiffness in the adenvirus/BMP-6osteotomies were equivalent to normal rabbit ulnas at both these timepoints. Maximum torsional strength for the contralateral surgicalcontrols was 44% and 66% of value for normal rabbit ulnas at 6 and 8weeks after creating the osteotomy. Torsional stiffness was 56% and 72%of the value for normal rabbit ulnas at 6 and 8 weeks after creating theosteotomy. Torsional strength and stiffness were similar in theadenvirus/GFP limbs compared to the contralateral surgical controls at 6weeks after creating the osteotomy.

The results of this study indicate that percutaneous injection ofadenovirus/BMP-6 administered one week after surgery acceleratesosteotomy healing in the rabbit ulna model. There was no effect ofadministering the adenovirus without BMP-6. The use of adenoviruscontaining cDNA for BMP-6 represents a potential injectable treatmentfor accelerating closed fracture repair in humans. TABLE 1 TorsionalStrength (Nm: Mean ± SD) Time AdenoBMP-6 Surgical CT AdenoGFP SurgicalCT Normal 6 weeks 0.63 ± 0.21 0.29 ± 0.26 0.32 ± 0.23 0.29 ± 0.18 0.66 ±0.15 8 weeks 0.67 ± 0.20 0.43 ± 0.17 0.66 ± 0.15

TABLE 2 Torsional Stiffness (Nm/deg: Mean ± SD) Time AdenoBMP-6 SurgicalCT AdenoGFP Surgical CT Normal 6 weeks 0.036 ± 0.015 0.018 ± 0.017 0.017± 0.014 0.016 ± 0.012 0.032 ± 0.008 8 weeks 0.038 ± 0.016 0.023 ± 0.0120.032 ± 0.008

The foregoing descriptions detail presently preferred embodiments of thepresent invention. Numerous modifications and variations in practicethereof are expected to occur to those skilled in the art uponconsideration of these descriptions. Those modifications and variationsare believed to be encompassed within the claims appended hereto.

1-30. (canceled)
 31. A method for promoting osteogenesis in a patientcomprising systemic administration of an effective amount of acomposition comprising an osteogenic protein.
 32. A method for promotingfracture repair in a patient comprising systemic administration of aneffective amount of a composition comprising an osteogenic protein. 33.The method of claim 31 or claim 32, wherein the osteogenic protein isselected from the group consisting of BMP-2, BMP-4, BMP-5, BMP-6, BMP-7,BMP-10, BMP-12, BMP-13, BMP-15, BMP-16, and MP52.
 34. The method ofclaim 33, wherein the osteogenic protein is BMP-2.
 35. The method ofclaim 33, wherein the osteogenic protein is BMP-4.
 36. The method ofclaim 33, wherein the osteogenic protein is BMP-5.
 37. The method ofclaim 33, wherein the osteogenic protein is BMP-6.
 38. The method ofclaim 33, wherein the osteogenic protein is BMP-7.
 39. The method ofclaim 33, wherein the osteogenic protein is BMP-10.
 40. The method ofclaim 33, wherein the osteogenic protein is BMP-12.
 41. The method ofclaim 33, wherein the osteogenic protein is BMP-13.
 42. The method ofclaim 33, wherein the osteogenic protein is BMP-15.
 43. The method ofclaim 33, wherein the osteogenic protein is BMP-16.
 44. The method ofclaim 33, wherein the osteogenic protein is MP52.